Washing appliance having a recirculation circuit

ABSTRACT

A washing appliance includes a treating chamber, a sprayer emitting liquid into the treating chamber, and a recirculation circuit including a centrifugal separator and an electrocoagulation unit both fluidly coupled to the recirculation circuit.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority to U.S. Provisional Patent ApplicationNo. 62/464,405, filed Feb. 28, 2017, which is incorporated herein byreference in its entirety.

BACKGROUND

Conventional automatic cleaning appliances, such as washing machines,dishwashers, and the like, involve the mixing of treating chemistry withwater to create a wash liquid or rinse liquid to facilitate the cleaningprocess. Soils can be loosened during the cleaning process, and variousmethods exist to remove such soils from the wash or rinse liquid duringthe cleaning process.

BRIEF SUMMARY

In one aspect, the disclosure relates to a washing appliance including atub at least partially defining a treating chamber with an accessopening, a sprayer emitting liquid into the treating chamber, arecirculation circuit fluidly coupling the treating chamber to thesprayer, a centrifugal separator (CS) fluidly coupled to therecirculation circuit, and an electrocoagulation unit (EU) fluidlycoupled to the recirculation circuit.

In another aspect, the disclosure relates to a method of treating atleast one of laundry or dishes in a treating chamber of an appliance.The method includes recirculating liquid through the treating chamber,centrifugally removing particles greater than a predetermined size fromthe liquid during recirculation of the liquid, and coagulating particlesgreater than the predetermined size in the liquid during recirculationof the liquid.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a schematic view of an exemplary washing appliance inaccordance with various aspects of the present disclosure.

FIG. 2 is a diagram of a recirculation circuit in the washing applianceof FIG. 1.

FIG. 3 illustrates the exemplary washing appliance of FIG. 1 in the formof a dishwasher.

FIG. 4 illustrates the exemplary washing appliance of FIG. 1 in the formof a clothes washer.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a washing appliance 10, which willnot be described in detail except as necessary for a completeunderstanding of the disclosure. It should be understood that thewashing appliance 10 can include a clothes washer or dishwasher, andthat the various aspects in the present disclosure can be used in anysuitable washing appliance, including a vertical-axis clothes washer,horizontal-axis clothes washer, combination washer-dryer, freestandingdishwasher, or under-counter dishwasher, in non-limiting examples.

The washing appliance 10 can include a cabinet 12 defining an interiorand an access opening 18 of the washing appliance 10, a tub 14 providedwithin the cabinet 12 and at least partially defining a treating chamber16 for receiving articles for treatment, such as dishes or laundry. Adoor assembly 20 can be mounted to the cabinet 12 to selectively openand close the access opening 18 of the tub 14 while also providingaccess to the treating chamber 16 for the loading and unloading of theitems. The door assembly 20 can be hingedly connected with the cabinet12 or slidingly attached to a drawer slide system to selectively provideaccess to the treating chamber 16.

The washing appliance 10 can further include a fluid circuit 29including the treating chamber 16, at least one sprayer 31, a sump 32,and a drain pump 33. The fluid circuit 29 is illustrated herein as arecirculation circuit 30 also having a recirculation pump 34 and a reusetank 35. The sprayer 31 can provide water to the treating chamber 16,after which the water can flow into the sump 32 where it can becollected in the reuse tank 35 and directed back to the sprayer 31 bythe recirculation pump 34. It is also contemplated that the drain pump33 can be fluidly coupled to the reuse tank 35 to drain collected water.In another example the fluid circuit 29 can optionally be anon-recirculating fluid circuit, where water can flow from the sprayer31 into the treating chamber 16 and move into the sump 32 before beingdrained by the drain pump 33.

A filtration system 40 for the washing appliance 10 can be fluidlycoupled to the circuit 30 and can include a coarse filter 41, a particlefilter 42, an electrocoagulation unit (EU) 50, and a centrifugalseparator (CS) 60. The coarse filter 41 can include a wire or plasticmesh capable of capturing large particles/soils, while the particlefilter 42 can include an ultrafiltration filter or nanofiltration filtercapable of trapping smaller particles down to 1.0 μm or 1.0 nm in size,respectively. The centrifugal separator 60, illustrated here as ahorizontal centrifuge and seen in further detail in FIG. 2, can includea cone-shaped body 61 and particle reservoir 62. The body 61 can rotateabout a central axis and form a rotating column of water at a speed suchthat soil particles of a predetermined size or density within the watercan undergo centrifugation, moving outward for collection in theparticle reservoir 62. The electrocoagulation unit 50, also seen infurther detail in FIG. 2, can include any standard/known EU wherein achamber 51 containing a series of charged plates/electrodes 52 can beused to apply an electrical charge to water in the chamber. In apreferred example the electrodes 52 can be made of graphite, however anymaterial suitable for the electrode environment can be used, includingaluminum. In operation, smaller dissolved soils in the EU 50, innon-limiting examples such as particles in colloidal suspension oroxidized metal ions, can coagulate and form larger particles which canbe more easily removed by the centrifugal separator 60.

The filtration system 40 can be fluidly coupled to the circuit 30 suchthat the electrocoagulation unit 50 is positioned upstream of thecentrifugal separator 60. There can be a water shear present within therecirculation pump 34 that can break apart coagulated soils, and in apreferred embodiment the recirculation pump 34 can be positionedupstream of both the CS 60 and EU 50 so as not to counter the action ofthe electrocoagulation unit 50. The coarse filter 41 can be positionedbetween the treating chamber 16 and sump 32, and the particle filter 42can be positioned on a separate fluid branch wherein a portion of thewater in the circuit 30 can flow through the particle filter 42 asshown. The particle filter 42 can be placed downstream of thecentrifugal separator 60 in a non-limiting example.

In addition, a valve or set of valves 70 can be coupled to therecirculation circuit 30. A valve 70 can be connected to the particlereservoir 62 to selectively remove soils collected in the reservoir 62,or connected to the drain pump 33 to selectively drain water from thetreating chamber 16 or reuse tank 35, or connected to the particlefilter 42 to selectively remove additional soils from the water, innon-limiting examples. The valves 70 can optionally be used toselectively direct water to the reuse tank 35.

FIG. 2 illustrates the circuit, illustrated here as the recirculationcircuit 30. In operation, liquid can be supplied to the treating chamber16 through the sprayer 31, after which it flows through the sump 32,particle filter 42 and optionally into the reuse tank 35, and therecirculation pump 34 can also return the liquid back into the treatingchamber 16. In addition, water from the treating chamber 16 canoptionally be drained by the drain pump 33. The recirculation pump 34can also direct at least a portion of the supplied liquid, or at least aportion of the recirculated liquid, to the electrocoagulation unit 50 inorder to coagulate soils into larger particles. The liquid andcoagulated particles can then move into the centrifugal separator 60,where the coagulated particles can be collected in the particlereservoir 62 and drained by the drain pump 33 while the purified liquidcan move into the reuse tank 35. At least a portion of the purifiedliquid from the centrifugal separator 60 can also be directed throughthe particle filter 42 to remove particles of a size small enough toremain in the water during centrifugation.

It is contemplated that during a wash cycle, the electrocoagulation unit50 can be switched off to prevent any undesired breakdown of treatingchemistry in the wash liquor such that water, treating chemistry, andsoils can flow through the EU 50 and remove buildup on the electrodes.The centrifugal separator 60 downstream of the EU 50 can remove soils,treating chemistry, and electrode buildup such that water flowingthrough the recirculation circuit 30 during a wash phase can be ofsufficient quality to be used in a later rinse phase.

It is further contemplated that during a rinse cycle, theelectrocoagulation unit 50 can be switched on to aid the centrifugalseparator 60 in purifying the water in the recirculation circuit 30. Thepolarity of the electrodes 52 in the EU 50 can be repeatedly reversed toprevent buildup on the electrodes 52, and in one non-limiting examplethe polarity can be reversed every sixty seconds. Water can then flowinto the centrifugal separator 60 in order to collect coagulated soilsas described above.

It can be appreciated that size of the particles generated by theelectrocoagulation unit 50 can be selected by modifying operatingparameters of the electrocoagulation unit 50 such as, but not limitedto, the electrode voltage or rate of polarity reversal. Similarly, theefficacy of particle settling by the centrifugal separator 60 can dependon parameters such as, but not limited to, the size, mass, or density ofsoil particles, or the rotational velocity of the liquid. Particles witha larger mass or density compared to the surrounding liquid can settleout of the liquid at a faster rate, and it can therefore be advantageousto coagulate smaller soil particles into larger ones by operating theelectrocoagulation unit 50 before directing liquid and soils into thecentrifugal separator 60 for more efficient removal of soils. In thismanner, the larger soils can be removed from the liquid by theelectrocoagulation unit 50 and centrifugal separator 60 while smallersoils can be collected by the particle filter 42, preventing unnecessaryclogging of the particle filter 42 by larger soil particles in theliquid and extending the useful lifetime of the particle filter 42.

It can be further appreciated that purifying wash water for use in arinse cycle, or purifying rinse water during a rinse cycle, can allowfor a reduction in total water usage by the washing appliance 10 whichcan also reduce the cost to the consumer for operating the washingappliance 10.

Referring now to FIG. 3, another washing appliance is illustrated in theform of a dishwasher 111. The dishwasher 111 is similar to the washingappliance 10; therefore, like parts will be identified with likenumerals increased by 100, with it being understood that the descriptionof the like parts of the washing appliance 10 applies to the dishwasher111, unless otherwise noted.

In the example of FIG. 3, the dishwasher 111 can include a cabinet 112defining an interior of the dishwasher 111 and including a frame, withor without panels mounted to the frame. An open-faced tub 114 can beprovided within the cabinet 112 and can at least partially define atreating chamber 116, having an open face, for washing dishes. A doorassembly 120 can be movably mounted to the dishwasher 111 for movementbetween opened and closed positions to selectively open and close theopen face of the tub 114. Thus, the door assembly provides accessibilityto the treating chamber 116 for the loading and unloading of dishes orother washable items.

It should be appreciated that the door assembly 120 can be secured tothe lower front edge of the cabinet 112 or to the lower front edge ofthe tub 114 via a hinge assembly (not shown) configured to pivot thedoor assembly 120. When the door assembly 120 is closed, user access tothe treating chamber 116 can be prevented, whereas user access to thetreating chamber 116 can be permitted when the door assembly 120 isopen.

Dish holders, illustrated in the form of upper and lower dish racks 180,181 are located within the treating chamber 116 and receive dishes forwashing. The upper and lower racks 180, 181 are typically mounted forslidable movement in and out of the treating chamber 116 for ease ofloading and unloading. Other dish holders can be provided, such as asilverware basket. As used in this description, the term “dish(es)” isintended to be generic to any item, single or plural, that can betreated in the dishwasher 111, including, without limitation, dishes,plates, pots, bowls, pans, glassware, and silverware.

A set of sprayers 131 provided for spraying liquid in the treatingchamber 116 and is provided in the form of a first lower spray assembly131A, a second lower spray assembly 131B, a rotating mid-level spray armassembly 131C, and/or an upper spray arm assembly 131D. Upper sprayer131D, mid-level rotatable sprayer 131C and lower rotatable sprayer 131Acan be located, respectively, above the upper rack 180, beneath theupper rack 180, and beneath the lower rack 181 and are illustrated asrotating spray arms. The second lower spray assembly 131B is illustratedas being located adjacent the lower dish rack 181 toward the rear of thetreating chamber 116.

A recirculation circuit 130 can be provided for recirculating liquidfrom the treating chamber 116 to the set of sprayers 131. Therecirculation circuit 130 can include a sump 132, a drain pump 133, arecirculation pump 134, and a reuse tank 135. The sump 132 can collectthe liquid sprayed in the treating chamber 116 and can be formed by asloped or recess portion of a bottom wall of the tub 114. The drain pump133 can draw liquid from the sump 132 and pump the liquid out of thedishwasher 110 to a household drain line (not shown). The recirculationpump 134 can draw liquid from the sump 132, and the liquid can besimultaneously or selectively pumped through a supply tube 182 to theset of sprayers 131 for selective spraying. While not shown, a liquidsupply system can include a water supply conduit coupled with ahousehold water supply for supplying water to the treating chamber 116.

A filtration system 140 can be fluidly coupled to the recirculationcircuit 130 and include a coarse filter 141, a particle filter 142, anelectrocoagulation unit (EU) 150 and a centrifugal separator (CS) 160. Aset of valves 170 can also be coupled to the recirculation circuit 130to selectively remove soils collected the CS 160, selectively supplywater to or drain water from the treating chamber 116 or reuse tank 135,or selectively remove additional soils from the water via the particlefilter 142, in non-limiting examples. It can be appreciated thatoperation of the EU 150 and CS 160 can coagulate and remove soils withinthe recirculation circuit 130 in a manner similar to that described inFIG. 2.

Turning to FIG. 4, another washing appliance is illustrated in the formof a clothes washer 211. The clothes washer 211 is similar to thewashing appliance 10; therefore, like parts will be identified with likenumerals increased by 100, with it being understood that the descriptionof the like parts of the washing appliance 10 applies to the clotheswasher 211, unless otherwise noted.

The washing appliance of FIG. 4 is illustrated as a clothes washer 211,which can include a structural support system including a cabinet 212which defines a housing within which a laundry holding system resides.The cabinet 212 can be a housing having a chassis and/or a frame,defining an interior enclosing components typically found in aconventional washing machine, such as motors, pumps, fluid lines,controls, sensors, transducers, and the like. Such components will notbe described further herein except as necessary for a completeunderstanding of the disclosure.

The laundry holding system includes a tub 214 supported within thecabinet 212 by a suitable suspension system and a drum 213 providedwithin the tub 214, the drum 213 defining at least a portion of alaundry treating chamber 216. The drum 213 can include a plurality ofperforations 219 such that liquid can flow between the tub 214 and thedrum 213 through the perforations 219. A plurality of baffles 222 can bedisposed on an inner surface of the drum 213 to lift the laundry loadreceived in the treating chamber 216 while the drum 213 rotates. It isalso within the scope of the disclosure for the laundry holding systemto include only a tub with the tub defining the laundry treatingchamber.

The laundry holding system can further include a door 220 which can bemovably mounted to the cabinet 212 to selectively close both the tub 214and the drum 213. A bellows 226 can couple an open face of the tub 214with the cabinet 212, with the door 220 sealing against the bellows 226when the door 220 closes the tub 214.

The clothes washer 211 can further include a suspension system 228 fordynamically suspending the laundry holding system within the structuralsupport system.

The clothes washer 211 can further include a liquid supply system forsupplying water to the clothes washer 211 for use in treating laundryduring a cycle of operation. The liquid supply system can include asource of water, such as a household water supply 239, which can includeseparate valves 243 and 244 for controlling the flow of hot and coldwater, respectively. Water can be supplied through an inlet conduit 245directly to the tub 214 by controlling first and second divertermechanisms 246 and 247, respectively. The diverter mechanisms 246, 247can be a diverter valve having two outlets such that the divertermechanisms 246, 247 can selectively direct a flow of liquid to one orboth of two flow paths. Water from the household water supply 239 canflow through the inlet conduit 245 to the first diverter mechanism 246which can direct the flow of liquid to a supply conduit 252. The seconddiverter mechanism 247 on the supply conduit 252 can direct the flow ofliquid to a tub outlet conduit 254 which can be provided with a spraynozzle or sprayer 231 configured to spray the flow of liquid into thetub 214. In this manner, water from the household water supply 239 canbe supplied directly to the tub 214.

The clothes washer 211 can also be provided with a dispensing system fordispensing treating chemistry to the treating chamber 216 for use intreating the laundry according to a cycle of operation. The dispensingsystem can include a dispenser 263 which can be a single use dispenser,a bulk dispenser or a combination of a single and bulk dispenser.

Regardless of the type of dispenser used, the dispenser 263 can beconfigured to dispense a treating chemistry directly to the tub 214 ormixed with water from the liquid supply system through a dispensingoutlet conduit 264. The dispensing outlet conduit 64 can include adispensing nozzle 266 configured to dispense the treating chemistry intothe tub 214 in a desired pattern and under a desired amount of pressure.For example, the dispensing nozzle 266 can be configured to dispense aflow or stream of treating chemistry into the tub 214 by gravity, i.e. anon-pressurized stream. Water can be supplied to the dispenser 263 fromthe supply conduit 252 by directing the diverter mechanism 247 to directthe flow of water to a dispensing supply conduit 268.

Non-limiting examples of treating chemistries that can be dispensed bythe dispensing system during a cycle of operation include one or more ofthe following: water, enzymes, fragrances, stiffness/sizing agents,wrinkle releasers/reducers, softeners, antistatic or electrostaticagents, stain repellants, water repellants, energy reduction/extractionaids, antibacterial agents, medicinal agents, vitamins, moisturizers,shrinkage inhibitors, and color fidelity agents, and combinationsthereof.

The clothes washer 211 can also include a recirculation and drain systemfor recirculating liquid within the laundry holding system and drainingliquid from the clothes washer 211. Liquid supplied to the tub 214through tub outlet conduit 254 and/or the dispensing supply conduit 268typically enters a space between the tub 214 and the drum 213 and canflow by gravity to a sump 232 formed in part by a lower portion of thetub 214. The sump 232 can also be formed by a sump conduit 272 that canfluidly couple the lower portion of the tub 214 to a pump assembly 274.The pump assembly 274 can include a drain pump 233 directing liquid to adrain conduit 276, which can drain the liquid from the clothes washer211. The pump assembly 274 can also include a recirculation pump 234directing liquid to a recirculation conduit 278 or reuse tank 235 whichcan terminate at a recirculation inlet 279. The recirculation inlet 279can direct the liquid from the recirculation conduit 278 into the drum213. The recirculation inlet 279 can introduce the liquid into the drum213 in any suitable manner, such as by spraying, dripping, or providinga steady flow of liquid. In this manner, liquid provided to the tub 214,with or without treating chemistry can be recirculated into the treatingchamber 216 for treating the laundry within. In this manner the treatingchamber 216, sprayer 231, sump 232, drain pump 233, recirculation pump234, and reuse tank 235 can define at least a portion of a recirculationcircuit 230 in the clothes washer 211.

The clothes washer 211 can further include a filtration system 240fluidly coupled to the recirculation circuit 230. The filtration system240 include a coarse filter 241, a particle filter 242, anelectrocoagulation unit (EU) 250 and a centrifugal separator (CS) 260. Aset of valves 270 can also be coupled to the recirculation circuit 130to selectively remove soils collected the CS 260, selectively supplywater to or drain water from the treating chamber 216 or reuse tank 235,or selectively remove additional soils from the water via the particlefilter 242, in non-limiting examples. It can be appreciated thatoperation of the EU 250 and CS 260 can coagulate and remove soils withinthe recirculation circuit 230 in a manner similar to that described inFIG. 2.

The liquid supply and/or recirculation and drain system can be providedwith a heating system which can include one or more devices for heatinglaundry and/or liquid supplied to the tub 214, such as a steam generator283 and/or a sump heater 285. Liquid from the household water supply 239can be provided to the steam generator 283 through the inlet conduit 245by controlling the first diverter mechanism 246 to direct the flow ofliquid to a steam supply conduit 286. Steam generated by the steamgenerator 283 can be supplied to the tub 214 through a steam outletconduit 287. The steam generator 283 can be any suitable type of steamgenerator such as a flow through steam generator or a tank-type steamgenerator. Alternatively, the sump heater 285 can be used to generatesteam in place of or in addition to the steam generator 283. In additionor alternatively to generating steam, the steam generator 283 and/orsump heater 285 can be used to heat the laundry and/or liquid within thetub 214 as part of a cycle of operation.

Additionally, the liquid supply and recirculation and drain system candiffer from the configuration shown in FIG. 1, such as by inclusion ofother valves, conduits, treating chemistry dispensers, sensors, such aswater level sensors and temperature sensors, and the like, to controlthe flow of liquid through the clothes washer 211 and for theintroduction of more than one type of treating chemistry.

The clothes washer 211 also includes a drive system for rotating thedrum 213 within the tub 214. The drive system can include a motor 288,which can be directly coupled with the drum 213 through a drive shaft290 to rotate the drum 213 about a rotational axis during a cycle ofoperation. The motor 288 can be a brushless permanent magnet (BPM) motorhaving a stator 292 and a rotor 294. Alternately, the motor 288 can becoupled to the drum 213 through a belt and a drive shaft to rotate thedrum 213, as is known in the art. Other motors, such as an inductionmotor or a permanent split capacitor (PSC) motor, can also be used. Themotor 288 can rotate the drum 213 at various speeds in either rotationaldirection.

The clothes washer 211 also includes a control system for controllingthe operation of the clothes washer 211 to implement one or more cyclesof operation. The control system can include a controller 296 locatedwithin the cabinet 212 and a user interface 298 that is operably coupledwith the controller 296. The user interface 298 can include one or moreknobs, dials, switches, displays, touch screens and the like forcommunicating with the user, such as to receive input and provideoutput. The user can enter different types of information including,without limitation, cycle selection and cycle parameters, such as cycleoptions.

The controller 296 can include the machine controller and any additionalcontrollers provided for controlling any of the components of theclothes washer 211. For example, the controller 96 can include themachine controller and a motor controller. Many known types ofcontrollers can be used for the controller 296. It is contemplated thatthe controller is a microprocessor-based controller that implementscontrol software and sends/receives one or more electrical signalsto/from each of the various working components to effect the controlsoftware. As an example, proportional control (P), proportional integralcontrol (PI), and proportional derivative control (PD), or a combinationthereof, a proportional integral derivative control (PID control), canbe used to control the various components.

To the extent not already described, the different features andstructures of the various embodiments can be used in combination witheach other as desired. That one feature is not be illustrated in all ofthe embodiments is not meant to be construed that it cannot be, but isdone for brevity of description. Thus, the various features of thedifferent embodiments can be mixed and matched as desired to form newembodiments, whether or not the new embodiments are expressly described.

While the disclosure has been specifically described in connection withcertain specific embodiments thereof, it is to be understood that thisis by way of illustration and not of limitation. Reasonable variationand modification are possible within the scope of the forgoingdisclosure and drawings without departing from the spirit of thedisclosure which is defined in the appended claims.

This written description uses examples to disclose embodiments of theinvention, and also to enable any person skilled in the art to practiceembodiments of the invention, including making and using any devices orsystems and performing any incorporated methods. The patentable scope ofthe invention is defined by the claims, and can include other examplesthat occur to those skilled in the art. Such other examples are intendedto be within the scope of the claims if they have structural elementsthat do not differ from the literal language of the claims, or if theyinclude equivalent structural elements with insubstantial differencesfrom the literal languages of the claims.

What is claimed is:
 1. A washing appliance comprising: a tub at leastpartially defining a treating chamber with an access opening; a sprayeremitting liquid into the treating chamber; a recirculation circuitfluidly coupling the treating chamber to the sprayer; a centrifugalseparator (CS) fluidly coupled to the recirculation circuit; and anelectrocoagulation unit (EU) fluidly coupled to the recirculationcircuit.
 2. The washing appliance of claim 1 further comprising arecirculation pump fluidly coupled to the recirculation circuit.
 3. Thewashing appliance of claim 2 wherein the EU is fluidly coupled to therecirculation circuit upstream of the CS.
 4. The washing appliance ofclaim 3 wherein the CS removes particles greater than a predeterminedsize.
 5. The washing appliance of claim 4 wherein the EU generatesparticles greater than the predetermined size.
 6. The washing applianceof claim 5 wherein the CS and EU are fluidly coupled to therecirculation circuit downstream of the recirculation pump.
 7. Thewashing appliance of claim 1 wherein the CS removes particles of a sizegreater than a predetermined size and the EU generates particles greaterthan the predetermined size.
 8. The washing appliance of claim 7 furthercomprising a particle filter fluidly coupled to the recirculationcircuit and removing particles of a size less than the predeterminedsize.
 9. The washing appliance of claim 8 wherein the particle filter isone of an ultrafiltration or nanofiltration filter.
 10. The washingappliance of claim 1 further comprising a reuse tank fluidly coupled tothe recirculation circuit.
 11. The washing appliance of claim 1 whereinthe CS comprises a particle reservoir storing centrifugally removedparticles.
 12. The washing appliance of claim 11 further comprising adrain pump fluidly coupled to the particle reservoir.
 13. The washingappliance of claim 1 wherein the washing appliance comprises at leastone of a clothes washer or a dishwasher.
 14. A method of treating atleast one of laundry or dishes in a treating chamber of an appliance,the method comprising: recirculating liquid through the treatingchamber; centrifugally removing particles greater than a predeterminedsize from the liquid during recirculation of the liquid; and coagulatingparticles greater than the predetermined size in the liquid duringrecirculation of the liquid.
 15. The method of claim 14 wherein thecoagulating occurs downstream of the centrifugally removing.
 16. Themethod of claim 15 wherein the coagulating comprising coagulatingparticles of a size smaller than the predetermined size.
 17. The methodof claim 16 further comprising after the centrifugally removing andbefore the coagulation, filtering a portion of the liquid to removeparticles less than the predetermined size.
 18. The method of claim 17further comprising storing at least some of the portion of the liquidfor reuse.
 19. The method of claim 16 further comprising draining thecentrifugally removed particles.
 20. The method of claim 19 furthercomprising using the liquid for both a wash phase and a rinse phase.